https://ia600805.us.archive.org/26/items/airlinescustomer-cares/United_Airlines_Official_CUSTOMER_Service_Contact_List.pdf
https://ia600405.us.archive.org/28/items/deltcustomercare/Delta_Airlines_Official_CUSTOMER_Service_Contact_List.pdf
https://ia600901.us.archive.org/13/items/aacustomer-services/American_Airlines_Official_CUSTOMER_Service_Contact_List.pdf